Questions about semantics for First-Order Logic

What are semantics in first-order logic?

Semantics. An interpretation of a first-order language assigns a denotation to each non-logical symbol in that language. It also determines a domain of discourse that specifies the range of the quantifiers.

How tell and ask are used in first-order logic?

The syntax of FOL determines which collection of symbols is a logical expression in first-order logic.
Basic Elements of First-order logic:

Constant 1, 2, A, John, Mumbai, cat,….
Variables x, y, z, a, b,….
Predicates Brother, Father, >,….
Function sqrt, LeftLegOf, ….
Connectives ∧, ∨, ¬, ⇒, ⇔

What is first-order and second order logic?

First-order logic uses only variables that range over individuals (elements of the domain of discourse); second-order logic has these variables as well as additional variables that range over sets of individuals.

Which is not familiar connectives in first-order logic?

Which is not Familiar Connectives in First Order Logic? Explanation: “not” is coming under propositional logic and is therefore not a connective.

Is first-order logic consistent?

By PROPOSITION 3.5 we know that a set of first-order formulae T is consistent if and only if it has a model, i.e., there is a model M such that M N T. So, in order to prove for example that the axioms of Set Theory are consistent we only have to find a single model in which all these axioms hold.